At present, in a GSM/EDGE Radio Access Network, GERAN, it is possible to configure multiple Common Control Channels, CCCHs, in a cell. The CCCHs are used by the GERAN network to perform control of the Mobile Stations, MSs, in the cells of the GERAN network.
A mobile station, an MS, in a GERAN cell will “camp” on, i.e. be attached to, one of the CCCHs which are configured for the cell of the MS, as determined by the so called “paging group” to which the MS belongs, which in turn is determined by the MS's International Mobile Subscriber Identity, its IMSI.
The current method, i.e. the one described above, of assigning MSs in a cell to one of a plurality of CCCHs in a cell has some negative performance implications: First of all, there is a risk of the MSs in a cell being unevenly spread among the CCCHs in the cell, and secondly, even in the case of severely uneven spread of the MSs among the CCCHs, an overloaded CCCH can't be offloaded by the other CCCHs.
Thus, an attempt to alleviate possible overloading of one or more CCCHs in a cell by increasing the number of CCCHs in the cell will not be a certain way of overcoming the problem, since configuring e.g. 4 CCCHs in a cell is not equivalent to increasing the CCCH capacity by a factor of 4.